=over

=item %^H
X<%^H>

The C<%^H> hash provides the same scoping semantic as C<$^H>.  This makes
it useful for implementation of lexically scoped pragmas.  See
L<perlpragma>.   All the entries are stringified when accessed at
runtime, so only simple values can be accommodated.  This means no
pointers to objects, for example.

When putting items into C<%^H>, in order to avoid conflicting with other
users of the hash there is a convention regarding which keys to use.
A module should use only keys that begin with the module's name (the
name of its main package) and a "/" character.  For example, a module
C<Foo::Bar> should use keys such as C<Foo::Bar/baz>.

This variable was added in Perl v5.6.0.

=back